Deep brain stimulation (DBS) in the subthalamic nucleus (STN) and other forms of neuromodulation are effective and safe surgical procedures that have been shown to reduce the motor dysfunction of advanced Parkinson's disease (PD) patients. Bilateral DBS refers to stimulation on both sides of the brain, while unilateral DBS refers to stimulation on one side of the brain. Bilateral and unilateral DBS typically target one of three areas, including the STN, GPI, VIM. Bilateral STN DBS has been associated with declines in cognitive and cognitive-motor functioning. DBS is similarly used to treat other neuro-degenerative diseases including cognitive, motor, and cognitive-motor disorders, but presently used stimulation parameters result in detrimental side effects.